May i get some help for my assignment please

i am creating a encode / decode program for my school assignment, i am in year 12. i need help with my pseodocode for my search & save parts in my assignment.

The search part is where i have 2 empty text boxes, the user inputs a text for example he types in A then clicks search & in the text box unDerneath it will count how many A there is in the Decoded / encoded text box & display the number.

For the save part... i want to be able to let the user click save & then will be able to save to the Decoded / encoded message in a text file.

i currently have the following :

BEGIN linearsearch
Get the string
Match adjacent character
Display result

thats for the search part.... but i Dont know how to change it.
please help.

for the Save part i got currently no pseuDocode